1. Field of the Invention
The present invention relates to an apparatus and method for transmitting/receiving a packet in a mobile communication system. More particularly, the present invention relates to an apparatus and method for transmitting/receiving a Forward Error Correction (FEC) packet in a mobile communication system.
2. Description of the Related Art
Mobile communication systems have evolved to provide large-capacity content as well as a voice service. Large-capacity content includes High Definition (HD) content, Ultra High Definition (UHD) content, and the like.
FIG. 1 illustrates a process for transmitting/receiving a packet in a mobile communication system according to the related art.
Referring to FIG. 1, a process for transmitting a packet by a transmitter, for example, a host A 110 to a receiver, for example, a host B 140 through a router #1 120 and a router #2 120 is illustrated. A layer structure of each entity is illustrated under each of the entities in FIG. 1. Both the host A 110 and the host B 140 have a layer structure including an application layer, a transport layer, an internet layer, and a link layer, and both the router #1 120 and the router #2 130 have a layer structure including an internet layer and a link layer. For example, the host A 110 is connected to the router #1 120 through an Ethernet, the router #1 120 is connected to the router #2 130 through a fiber and a satellite, and the router #2 130 is connected to the host B 140 through the Ethernet.
A data format processed in each layer is described in view of the host A 110.
If data 151 occurs in the application layer, the application layer transfers the data 151 to the transport layer. For example, the data 151 may be a Real Time Protocol (RTP) packet, or a Moving Picture Experts Group (MPEG) Media Transport (MMT) packet. The RTP packet represents a packet which is generated by packetizing data compressed in an Audio Video Codec (AV Codec) using RTP.
The transport layer generates a User Datagram Protocol (UDP) packet including a UDP header 161 and UDP data 163 by processing the data 151, and transfers the generated UDP packet to the internet layer. The internet layer generates an Internet Protocol (IP) packet including an IP header 171 and IP data 173 by processing the UDP packet, and transfers the generated IP packet to the link layer. The link layer generates a link packet including a frame header 181, frame data 183, and a frame footer 185 by processing the IP packet.
Mobile communication systems provide various large-capacity contents, so data congestion on a network has increased. As a result, content transmitted by a transmitter are not completely transferred to a receiver, and some of the content is lost en route.
In general, data is transmitted on a packet basis, and accordingly data loss is generated on a transmission packet basis. Accordingly, the receiver cannot receive a lost transmission packet, and thus cannot receive data within the lost transmission packet.
Accordingly, there is a need for a method for reducing data loss due to transmission packet loss. A typical example of the method is a Forward Error Correction (FEC) scheme. The FEC scheme generates a parity block by encoding a source block including a predetermined number of packets using an FEC encoding scheme thereby transmitting the source block and the parity block, so error correction capability may be enhanced. A block including the source block and the parity block is referred to as an FEC packet. Each packet included in the source block includes a header, and each of the headers includes the same Application Layer FEC (AL-FEC) signaling information for AL-FEC signaling.
When the FEC packet is transmitted/received as described above, a signaling overhead for transmitting/receiving the header included in each of the packets included in the source block occurs. The signaling overhead may result in an FEC packet transmission/reception process delay as well as reducing radio resource efficiency of a mobile communication system.
Therefore, a need exists for a method for transmitting/receiving an FEC packet in order to reduce a signaling overhead due to a header transmission/reception.